This disclosure relates generally to the field of computer graphics. More particularly, but not by way of limitation, it relates to technique for manipulating sprites in a rendering system for use with a graphics processor unit (GPU).
A sprite is a two-dimensional (2D) image or animation that is integrated into a larger scene. Sprites can be mapped into three-dimensional (3D) scenes. Sprites may be created from any source, including pre-rendered imagery, dynamic 3D graphics, vector art, and even text. As graphics processor units (GPUs) have become available, libraries of sprites and graphic processing routines have been developed to provide a rendering system that allows use of the power of GPUs for faster rendering of graphics instead of depending entirely on the processing power of common central processing units (CPUs). Generally both CPUs and GPUs are involved in graphics processing operations provided by these libraries, with much of the graphics processing handled by the GPUs.
These rendering systems typically represent graphics operations in a scene tree. The scene graph is a structure that arranges the logical and often (but not necessarily) spatial representation of a graphical scene. A scene graph is a collection of nodes in a graph or tree structure. A node may have many children but often only a single parent, with the effect of a parent applied to all its child nodes. An operation performed on a group automatically propagates its effect to all of its members. A common feature is the ability to group related shapes/objects into a compound object that can then be moved, transformed, selected, etc. as easily as a single object.